1. Field of the Invention
The invention relates to methods of making artificial airway devices, more specifically to methods of making supraglottic airways utilizing blow molding techniques
2. Description of Related Art
In general, supraglottic airways such as laryngeal masks allowing for both rapid lung ventilation and the insertion of medical instruments and tubes into the laryngeal openings of patients have been described in patents, such as U.S. Pat. No. 4,509,514 to Brain and U.S. Pat. Nos. 6,422,239 and 5,937,860 to Cook the entire disclosures of which are herein incorporated by reference. Laryngeal masks generally consist of two major components, a breathing tube and an inflatable shield, these devices are inserted into a patient's throat, and when properly positioned, cover the laryngeal opening. A seal is then formed around the circumference of the laryngeal opening by the inflation of a ring-like structure located toward the front of the mask (patient end). Inflation of the ring exerts pressure against the front, sides, and rear portions of the oropharynx, securing the device in place such that the laryngeal opening is positioned in alignment with a recessed cavity in the mask face. Extending from a point external to the oral cavity, the flexible breathing tube terminates within the recessed cavity, aligned axially with the laryngeal opening. The positioning of the flexible breathing tube allows the passage of endo-tracheal tubes or related medical instruments into the laryngeal opening, in addition to allowing for lung ventilation.
Supraglottic airways of this type are typically manufactured by one of two methods. One method involves forming the upper and lower portions of the inflatable peripheral portion of the mask and the base separately using various molding techniques. The two portions are then connected using heat, pressure, adhesive, or combinations of each. While this method has been successful, the parts must be glued together meaning that several process steps are necessary to manufacture a market-ready product and second, the later join results in a seam which results in a point of potentially compromised stability.
Supraglottic airways of this type have also been manufactured using injection molds including cores as discussed in U.S. patent application Ser. No. 10/691,399 the entire disclosure of which is herein incorporated by reference. While these methods have also been successful, they are often more expensive and slower than other molding techniques.